A podcast is a digital medium consisting of an episodic series of audio, digital radio, PDF, or ePub files subscribed to and downloaded through web syndication or streamed online to a computer or mobile device. The word is a neologism and portmanteau derived from "broadcast" and "pod" from the success of the iPod, as audio podcasts are often listened to on portable media players. Merriam Webster defines Podcast: a program made available in digital format for automatic download over the Internet. A list of all the audio or video files associated with a given series is maintained centrally on the distributor's server as a web feed, and the listener or viewer employs special client application software, known as a podcatcher, that can access this web feed, check it for updates, and download any new files in the series. This process can be automated so that new files are downloaded automatically, which may seem to the user as if the content is being broadcast or "pushed" to them. Files are stored locally on the user's computer or other device ready for offline use, giving simple and convenient access to the content.